Compilare: user.cpp: In function ‘int main()’: user.cpp:21:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("strmatch.in", "r", stdin); ^ user.cpp:22:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("strmatch.out", "w", stdout); ^ user.cpp:27:21: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%s%s", a, b); ^ In file included from /usr/include/string.h:642:0, from user.cpp:2: In function ‘void* memset(void*, int, size_t)’, inlined from ‘int main()’ at user.cpp:24:25: /usr/include/i386-linux-gnu/bits/string3.h:85:70: warning: call to void* __builtin___memset_chk(void*, int, unsigned int, unsigned int) will always overflow destination buffer [enabled by default] return __builtin___memset_chk (__dest, __ch, __len, __bos0 (__dest)); ^ In function ‘void* memset(void*, int, size_t)’, inlined from ‘int main()’ at user.cpp:25:25: /usr/include/i386-linux-gnu/bits/string3.h:85:70: warning: call to void* __builtin___memset_chk(void*, int, unsigned int, unsigned int) will always overflow destination buffer [enabled by default] return __builtin___memset_chk (__dest, __ch, __len, __bos0 (__dest)); ^